Water-tube boiler.



W. HOFF. WATER TUBE BoILBR.

APPLIUATION FILED MAY 10, 1911.

Patented Feb.23,1915.

' WILHELM HOPF,` 0F KIEL, GrERBlZAIN'Y,V ASSIGNOR T0 FRIED. KRUPP A KTIENGESELL,-

` SCHAFT GERMANIAWERFT,"OFKIEL-GAARDEN. GERMANY. y

WATER-TUBE BOILER.

mageos.-

To all whom it may concern: I

Be it known that I, WILHELM Herr, a citizen of the German Empire, residing 4at Kiel, Germany, have invented certain'new and useful Improvements in Water-Tube Boilers, of which the following is a specification.

This invention relates to a water tube boiler with narrow tubes, having at least one upper .water drum, two lower water drums and nests of narrow tubes connecting the upper and lower drums, together with two superheaters, said superheaters are arranged outside of the tube nests that close it from the fire.

This invention relates moreA particularly to the. arrangement of the yguiding walls for the heating gases, whereby it has been made possible in coperation with dampers in a boiler of very simple construction either to lead the heating gasesV by the superheaters of higher temperature or by entirely eX- cluding the superheaters.

Two constructional forms of a boiler according to this invention are shown on the accompanying drawings at Figures 1 and 2, both of which are vertical transverse sections of so much of the same as will be necessary for the purposes of this specification.

The boiler shown in Fig. l consists of an upper water drum A, which communicates by two nests of tubes B with two lower water drums C. Between the nests of tubes of tubes B and on each side of the boiler is arranged a superheater E, in front of each of which is placed a damper G, which can be moved into `a lower and an upper eXtreme position. Into the nests of tubes B are built guide `walls vfor the heating gases, which guide walls are made of lireproof ma terial (such as fire clay or the like). and consist of a longer portion F running longitudinally of the nest of tubes, and a shorter portion F1 lying atv right angles to the group. The portion F of the guide walls might also be a closed wall formed by a row of tubes, as is well known per se. The walls F1 and the dampers G are so arranged with relation to each other, that the dampers G when in the lower position, form a conl tinuation of the guide walls F1 for the heating ases.

heating gases sweep first through only the small number of inner rows of tubes shut off by the guide walls F and over the short upper parts of the remaining rows of tubes. They then pass through the' superheaters at still very highV temperatures andV after that sweep through the remaining rows of tubes in the group of tubes B. `When the dampers are in the upper position however, the superheaters are shut ofll by the dampers and the lire gases pass through the nests of tubes B only.

The difference between the boiler shown in Fig. 2 and the one above described is that two additional water drums A2 are provided.A These are'likewise connected to the lower water drums C2 by nests of tubes B2 into which the guide walls F2 for the heating gases are built. The arrangement of the guide walls F3 F2 for the heating gases in the central nests of tubes B3 and of the dampers G2, accords with that of the boiler shown in Fig. `l. A2 is the upper central drum and D2 is the furnace. i

When the dampers G2 are in the lower extreme position shown in the drawing, the heating gases sweep first through the small number of rows of the nests of tubes B2 ly- 'ing inside the walls F4 and over the short parts of the tubes lying above the walls F3, pass next in a very highly heated state, into the superheaters E2, then sweep through the remainder of the nests of tubes VB3 and after that pursue their way guided by the guide walls F2, through the nests B2, to which they give up the rest of the heat which they contain. When the dampers G are in their upper eXtreme position, the superheaters are shuty olf, and the heating gases pass through the nests of tubes B3 B2 only. The lower part F4 of the guide walls for the heating gases might also be formed by a tube wall. The guide walls F2 in the outer nests of tubes B2 might be omitted. Tn suchcase the uptake for the heating gases should be preferably placed at the upper end of the nests B2 between the upper water drum A3 and the superheater.

Having thus described the invention, what is claimed and desired to be secured by Letters Patent is:

1. In a water tube boiler, having a plurality of water drums symmetrically deposited in two layers, an even number below, and an odd number above, and a furnace be- Specificationy of Letters Patent. Patented Fey@ 23, 1915, A Application filed May 10, 1911. Serallio. 626,184.

tween the drums in the lower layer, the combination with nests of narrow tubes connecting the upper drums to' the lower drums, each nest comprising a plurality of parallel running tubes; of a superheater situated symmetrically 0n each side of the central upper drum placed so as not to come in Contact with said narrow tube nests; guide walls for the heating gases built intoy the central pair of tube nests, the lower part of said walls' runningy parallel to said narrow tubes and dividing them into two unequal bunches7 with Vthe fewest tubes innermost; the upper partsfof said guide walls diverging approximately at right angles across said tube nests ;;dampers constructed to have two eXtreme positions; forming continuations to said divergingguide walls when in the lower position, and standing at approximately right angles to said guide walls when in the upper position, saidguide walls and dampers, when in their lower position compellingfthe gases from the furnace to sweep through the smaller bunch of narrow water drums symmetrically disposed relative to said central drum; one pair of nests said lower drums parallel to said tube nests respectively, and dividing the tubes in each of said nests into a large and a small bunch, the larger bunches in each pair of nests lying adjacent each other; a third guide wall suspended from the roof of the boiler between said central drum and each of the upper side drums; supcrheaters situated symmetrically on both sides ol said central drum and between said third guide walls and a damper for each superheater situated WLHELM HOPF.

Witnesses JULIUs Rornn, PAUL Porrnnninoii.

Gopiresfof this patent may be obtained for five cents each, by addressing the Commissioner of Patents Y Washington, D. C. 

